Estimation of density of some bird species in thuong tien natural reserve, hoa binh province

MINISTRY OF AGRICULTURE AND RURAL DEVELOPMENT VIETNAM FORESTRY UNIVERSITY STUDENT THESIS ESTIMATION OF DENSITY OF SOME BIRD SPECIES IN THUONG TIEN NATURAL RESERVE, HOA BINH PROVINCE Major: Natural Resources Management (Advanced Curriculum) Code: D850101 Faculty: Forest Resources and Environmental Management Student: Nguyen Thi Ngoc Diep Student ID: 1153091135 Class: K56 Natural Resources Management Course: 2011 – 2015 Advanced Education Program Developed in Collaboration with Colorado State University, USA Supervisor: Assoc Prof Dr Vu Tien Thinh Hanoi, October 2015 ACKNOWLEDGEMENTS Firstly, I would like to express my sincere gratitude to my advisor Assoc Prof Dr Vu Tien Thinh for the continuous support of my thesis and related research, for his patience, motivation, and immense knowledge His guidance helped me in all the time of research and writing of this thesis I could not have imagined having a better advisor and mentor for my thesis Besides my advisor, I would like to thank various teachers of Vietnam Forestry University and Vietnam Forestry University for providing me opportunity, essential conditions and research facilities to conduct this thesis I also especially thank Prof Lee MacDonald for assisting me in the logical outline, structure and for valuable comments and discussions of final presentation It is lucky to learn from you as an academic professor, as a friend and as a father My sincere thanks also go to management committee, officers of Thuong Tien Natural reserve Without their precious support, I would not be possible to conduct this thesis Last but not the least, I would like to thank my family for supporting me spiritually throughout writing this thesis and my life in general During the implementation of the thesis, my research is inevitable shortcoming due to time and finance limitation, as well as human resources I look forward to receiving some comments from teachers for more completion Hanoi, October 2015 2i TABLE OF CONTENTS ACKNOWLEDGEMENTS i TABLE OF CONTENTS .ii LIST OF FIGURES iii LIST OF TABLES iv ABBREVIATIONS v ABSTRACT vi INTRODUCTION OBJECTIVES 2.1 General objective 2.2 Specific objective 3 METHODS 3.1 Study area 3.2 Data collection .6 3.3 Estimating detection probability 3.4 Estimating density of species RESULT 11 4.1 Describing field survey data 11 4.2 Modeling detection probability by distance 14 4.3 Estimating density of species in transects 20 DISCUSSION 22 CONCLUSION 25 REFERENCES 26 APPENDICES 27 ii LIST OF FIGURES Figure 3.1: Location of study area Figure 3.2: Simulating objects detected in line transects Figure 3.3: Distance sampling measurement from a line-transect within the study area Figure 4.1: Percentage of Black-crested bulbul detected by observation and hearing 12 Figure 4.2: Percentage of Puff-throated bulbul detected by observation and hearing 12 Figure 4.3: Percentage of Yellow-bellied warbler detected by observation and hearing 13 Figure 4.4: Uniform function for Black-crested bulbul 15 Figure 4.5: Half-normal function for Black-crested bulbul 15 Figure 4.6: Hazard-rate function for Black-crested bulbul 15 Figure 4.7: Negative exponential function for Black-crested bulbul 15 Figure 4.8: Uniform function for Puff-throated bulbul 17 Figure 4.9: Half-normal function for Puff-throated bulbul 17 Figure 4.10: Hazard-rate function for Puff-throated bulbul 17 Figure 4.11: Negative exponential function for Puff-throated bulbul 17 Figure 4.12: Uniform function for Yellow-bellied warbler 19 Figure 4.13: Half-normal function for Yellow-bellied warbler 19 Figure 4.14: Hazard-rate function for Yellow-bellied warbler 19 Figure 4.15: Negative exponential function for Yellow-bellied warbler 19 Figure 1: Black-crested bulbul (Pycnonotus melanicterus) 27 Figure 2: Puff-throated bulbul ( Alophoixus pallidus ) 28 Figure 3: Yellow-bellied warbler (Abroscopus superciliaris) 29 iii LIST OF TABLES Table 3.1: Field data sheets used to collect information Table 4.1: Number of Black-crested bulbul group, Puff-throated bulbul group and Yellowbellied warbler group detected by distance in the survey 11 Table 4.2: Evaluating functions used to model the detection probability for Black-crested bulbul 14 Table 4.3: Evaluating functions used to model the detection probability for Puff-throated bulbul 16 Table 4.4: Evaluating functions used to model the detection probability for Yellow-bellied warbler 18 Table 4.5: Estimated density of Black-crested bulbul for transects 20 Table 4.6: Estimated density of Puff-throated bulbul for transects 20 Table 4.7: Estimated density of Yellow-bellied warbler for transects 21 Table 5.1: Comparing density estimation results using distance sampling method and traditional method for Black-crested bulbul 22 Table 5.2: Comparing density estimation results using distance sampling method and traditional method for Puff-throated bulbul 23 Table 5.3: Comparing density estimation results using distance sampling method and traditional method for Yellow-bellied warbler 23 iv ABBREVIATIONS AIC Akaike’s Information Criterion CV Coefficient of variation LB Lower boundary UB Upper boundary v6 ABSTRACT Wildlife surveys are important to ecological studies as the knowledge of population size is fundamental for conservation and management purposes Application of quantitative methods for wildlife survey and monitoring to estimate population size, density is necessary In wildlife survey, individuals far from transect are likely to be not detected Therefore, density estimation using traditional methods is smaller than the reality In this study, data of Black-crested bulbul, Puff-throated bulbul and Yellow-bellied warbler collected in Thuong Tien Natural reserve is used to model the detection probability and then used to adjust the estimation of density Thuong Tien Natural reserve is located in Hoa Binh province, with total natural area of 7308 and characterized by evergreen closed forest ecosystem on mountains, with 2-3 storey structure The survey was conducted from late July to August with transects in regeneration forest With Blackcrested bulbul and Yellow-bellied warbler, Half-normal function best fit the variation of detection probability as distance increase and with Puff-throated bulbul, Hazard-rate is the selected function The detection probability of Black-crested bulbul is 0.55, Puff-throated bulbul is 0.42 and Yellow-bellied warbler is 0.46 The group density are 0.38 groups/ha for Black-crested bulbul, 0.66 groups/ha for Puff-throated bulbul, 0.52 groups/ha for Yellowbellied warbler If detection probability is not taken into account, the estimated density will be much smaller than the reality Therefore, estimation of detection probability that will be then used to adjust the density is crucial in wildlife survey and monitoring vi INTRODUCTION Thuong Tien Natural reserve is located in Thuong Tien commune (Kim Boi district) and Quy Hoa commune (Lac Son district) in Hoa Binh province, with total natural area of 7308 This area is characterized by evergreen closed forest ecosystem on mountains, with 2-3 storey structure In particular, Thuong Tien Natural reserve is also known as the gateway location of northwest ecoregions and falls in distribution range of many rare plant and animal species of Vietnam and the Indochina Peninsula Due to the high faunal diversity of the area, effective conservation and management are very important, especially for the wildlife species which are difficult to manage, including bird species In biodiversity monitoring, to be able to monitor and manage the species, managers need to know the diversity and have data of estimated density and population size of the species exactly So the application of quantitative methods for survey and monitoring to estimate population size, density is important Unlike plant, animal have many unique characteristics that make the estimation of density and population size difficult The biggest difficulty is that not all objects are detected in the survey area (detection probability